Moving blog within site

Sorry for resurrecting this old chestnut. I’ve seen this question asked before and thought it would be easy to reference old answers for the instructions. Poking around, this post is suggested on numerous occasions: https://codex.www.ads-software.com/Moving_WordPress#Moving_WordPress_Within_Your_Site

I’m using WP 2.8.5 and am trying to move my primary blog https://mysite.com to https://subdomain.myblog.com. I’ve followed the instructions — as I’ve understood them — twice and both times managed to wipe out my site. Thank goodness for backups!

I’ve noticed the instructions do not gibe with the version of WP I run, which makes me wonder if something else has changed that would cause these steps to be out of date.

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The direx say go to the general settings page and “In the box for WordPress address (URI): change the address to the new location of your main WordPress core files.” Then change the blog address URI.

(I’ve done some reading up on URIs, since I didn’t know the difference from URL, but still am not very clear. )

In any case, in my version of the WP settings page URIs are not requested, but instead asks for WordPress URL and Blog address URL. It says that these two items should match.

So, something has changed in the admin since the instructions were written. When I ignored the URI/URL discrepancy, entering https://subdomain.mysite.com in both fields, the site stopped cooperating.

The instructions say to not move the core files until after completing this step. But when I attempt to save the above change, the admin immediately throws an error back at me, saying the settings cannot be saved and to contact the admin. This kind of makes sense, since I’ve just told it that WP is living in a different location, only it isn’t, not yet.

It says do not look at your site at this point, but like Lot’s wife, I couldn’t resist. Content still appeared to be there, but styling was/is gone.

I tried the above steps again, but moved the core files before saving, and the site vanished all together, including the admin, which was fun.

So, first question: what has changed since the instructions were written? Would that affect the steps?

second question: URI vs URL. I’m moving the blog to the web address https://roadtrip.mysite.com. The core files will live at “/home/lisacrou/mysite.com/html/roadtrip” (which is where my host writes subdomains to). Rater than matching the two fields, should I put the latter in the WordPress address field? Possibly a dumb question, but thought I’d ask.

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Is there something obvious in the instructions I’m missing? Is there a more up-to-date tutorial somewhere? Any answers are appreciated.

~ lisa